In recent years, performance of information equipment has dramatically improved. As the power consumption of information equipment increases, it becomes more often that the information equipment needs to be charged up at places other than home. However, it is prohibited to charge up information equipment using a receptacle provided at a building in the town without permission. In order to avoid a battery of the information equipment from running out while on the go, it is necessary to always carry around a spare battery.
Various proposals have been made to eliminate such inconvenience. For example, Patent Literature (hereinafter, referred to as “PTL”) 1 discloses an electric charging terminal that bills a mobile terminal apparatus, which is registered in advance, when the registered mobile terminal apparatus is charged up.
Further, PTL 2 discloses a billing server which bills a user who charges up a mobile terminal from a receptacle for commercial use according to an amount of consumed power and pays an amount corresponding to the amount of consumed power to an account of an owner of the receptacle for commercial use providing power.
Further, PTL 3 discloses a receptacle billing apparatus which collects fee corresponding to the amount of consumed power from cash fed from a cash feeding port. Still further, PTL 4 discloses a mobile phone electric charging system which specifies a user of a mobile phone by exchanging information with the mobile phone and bills a user of the mobile phone for electric charging of the mobile phone.